the 1st page thing is more of a measure of how old the thread is. However on less trafficked sites and the less active sections the age is more important. Also Not all necros are bad sometimes it's done too prevent duplication of an older idea, but many are pointless.

The two-week thing is just something Silva made up a long time ago and nobody argued because (a) not a single other god damned person cares about necros besides him (which is why the smiley is based on his old usericon), and (b) they figured he was being intentionally vapid as a form of trolling, basing this on a body of previous evidence consisting of every other post he's ever made.

Robot Monkey's definition makes a lot more sense to me. If a thread's still on the first page, it's still on the radar and therefore "alive." If it drops off the page, it must be dead. To put it back on the first page is an act of necromancy. It (a) makes good sense and (b) makes silva wrong, so I like it on multiple levels.